// COPIED FROM Render.cpp in Box2D/Examples/TestBed/Framework

/*
* Copyright (c) 2006-2007 Erin Catto http://www.gphysics.com
*
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/


#include "PhysicsDebugDraw.h"

#include "Common.h"

#include <cstdio>
#include <cstdarg>

void DebugDraw::DrawPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color)
{
        glColor3f(color.r, color.g, color.b);
        glBegin(GL_LINE_LOOP);
        for (int32 i = 0; i < vertexCount; ++i)
        {
                glVertex2f(vertices[i].x, vertices[i].y);
        }
        glEnd();
}

void DebugDraw::DrawSolidPolygon(const b2Vec2* vertices, int32 vertexCount, const b2Color& color)
{
        glEnable(GL_BLEND);
        glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glColor4f(0.5f * color.r, 0.5f * color.g, 0.5f * color.b, 0.5f);
        glBegin(GL_TRIANGLE_FAN);
        for (int32 i = 0; i < vertexCount; ++i)
        {
                glVertex2f(vertices[i].x, vertices[i].y);
        }
        glEnd();
        glDisable(GL_BLEND);

        glColor4f(color.r, color.g, color.b, 1.0f);
        glBegin(GL_LINE_LOOP);
        for (int32 i = 0; i < vertexCount; ++i)
        {
                glVertex2f(vertices[i].x, vertices[i].y);
        }
        glEnd();
}

void DebugDraw::DrawCircle(const b2Vec2& center, float32 radius, const b2Color& color)
{
        const float32 k_segments = 16.0f;
        const float32 k_increment = 2.0f * b2_pi / k_segments;
        float32 theta = 0.0f;
        glColor3f(color.r, color.g, color.b);
        glBegin(GL_LINE_LOOP);
        for (int32 i = 0; i < k_segments; ++i)
        {
                b2Vec2 v = center + radius * b2Vec2(cosf(theta), sinf(theta));
                glVertex2f(v.x, v.y);
                theta += k_increment;
        }
        glEnd();
}

void DebugDraw::DrawSolidCircle(const b2Vec2& center, float32 radius, const b2Vec2& axis, const b2Color& color)
{
        const float32 k_segments = 16.0f;
        const float32 k_increment = 2.0f * b2_pi / k_segments;
        float32 theta = 0.0f;
        glEnable(GL_BLEND);
        glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glColor4f(0.5f * color.r, 0.5f * color.g, 0.5f * color.b, 0.5f);
        glBegin(GL_TRIANGLE_FAN);
        for (int32 i = 0; i < k_segments; ++i)
        {
                b2Vec2 v = center + radius * b2Vec2(cosf(theta), sinf(theta));
                glVertex2f(v.x, v.y);
                theta += k_increment;
        }
        glEnd();
        glDisable(GL_BLEND);

        theta = 0.0f;
        glColor4f(color.r, color.g, color.b, 1.0f);
        glBegin(GL_LINE_LOOP);
        for (int32 i = 0; i < k_segments; ++i)
        {
                b2Vec2 v = center + radius * b2Vec2(cosf(theta), sinf(theta));
                glVertex2f(v.x, v.y);
                theta += k_increment;
        }
        glEnd();

        b2Vec2 p = center + radius * axis;
        glBegin(GL_LINES);
        glVertex2f(center.x, center.y);
        glVertex2f(p.x, p.y);
        glEnd();
}

void DebugDraw::DrawSegment(const b2Vec2& p1, const b2Vec2& p2, const b2Color& color)
{
        glColor3f(color.r, color.g, color.b);
        glBegin(GL_LINES);
        glVertex2f(p1.x, p1.y);
        glVertex2f(p2.x, p2.y);
        glEnd();
}

void DebugDraw::DrawXForm(const b2XForm& xf)
{
        b2Vec2 p1 = xf.position, p2;
        const float32 k_axisScale = 0.4f;
        glBegin(GL_LINES);
        
        glColor3f(1.0f, 0.0f, 0.0f);
        glVertex2f(p1.x, p1.y);
        p2 = p1 + k_axisScale * xf.R.col1;
        glVertex2f(p2.x, p2.y);

        glColor3f(0.0f, 1.0f, 0.0f);
        glVertex2f(p1.x, p1.y);
        p2 = p1 + k_axisScale * xf.R.col2;
        glVertex2f(p2.x, p2.y);

        glEnd();
}

void DrawPoint(const b2Vec2& p, float32 size, const b2Color& color)
{
        glPointSize(size);
        glBegin(GL_POINTS);
        glColor3f(color.r, color.g, color.b);
        glVertex2f(p.x, p.y);
        glEnd();
        glPointSize(1.0f);
}

void DrawSegment(const b2Vec2& p1, const b2Vec2& p2, const b2Color& color)
{
        glColor3f(color.r, color.g, color.b);
        glBegin(GL_LINES);
        glVertex2f(p1.x, p1.y);
        glVertex2f(p2.x, p2.y);
        glEnd();
}

void DrawString(int /*x*/, int /*y*/, const char /* *string*/, ...)
{
        return;
        /*char buffer[128];

        va_list arg;
        va_start(arg, string);
        vsprintf_s(buffer, 128, string, arg);
        va_end(arg);

        glMatrixMode(GL_PROJECTION);
        glPushMatrix();
        glLoadIdentity();
        int w = glutGet(GLUT_WINDOW_WIDTH);
        int h = glutGet(GLUT_WINDOW_HEIGHT);
        gluOrtho2D(0, w, h, 0);
        glMatrixMode(GL_MODELVIEW);
        glPushMatrix();
        glLoadIdentity();

        glColor3f(0.9f, 0.6f, 0.6f);
        glRasterPos2i(x, y);
        int32 length = (int32)strlen(buffer);
        for (int32 i = 0; i < length; ++i)
        {
                glutBitmapCharacter(GLUT_BITMAP_8_BY_13, buffer[i]);
        }

        glPopMatrix();
        glMatrixMode(GL_PROJECTION);
        glPopMatrix();
        glMatrixMode(GL_MODELVIEW);*/
}

void DrawAABB(b2AABB* aabb, const b2Color& c)
{
        glColor3f(c.r, c.g, c.b);
        glBegin(GL_LINE_LOOP);
        glVertex2f(aabb->lowerBound.x, aabb->lowerBound.y);
        glVertex2f(aabb->upperBound.x, aabb->lowerBound.y);
        glVertex2f(aabb->upperBound.x, aabb->upperBound.y);
        glVertex2f(aabb->lowerBound.x, aabb->upperBound.y);
        glEnd();
}